1. Field of Invention
The present invention relates to an optical imaging system, and more particularly to an optical imaging system having multiple lens elements.
2. Related Prior Art
In recent years, with the rise of mobile electronics featuring camera functionalities, the demand for miniaturized camera lenses is boosted exponentially. Photo-sensing device (sensor) of ordinary photographing camera is commonly selected from charge coupled device (CCD) or complementary metal-oxide semiconductor (CMOS). In addition, as advanced semiconductor manufacturing technology enables the minimization of pixel size of sensors, the development of the miniaturized camera lenses is also heading toward the high pixel domain. Therefore, the standards for the imaging quality are rapidly raised.
U.S. Pat. No. 7,365,920 provides a miniature camera unit with a four-element lens assembly. The lens elements of the miniaturized camera are utilized in various portable electronics. However, due to the popularity of the mobile electronics such as smart phones and personal digital assistants (PDAs), the standards for the resolution and the imaging quality of the miniature camera lens assemblies have been raised, accordingly. The conventional four-element lens assembly cannot meet the requirement of the higher order camera lens module. Besides, the electronic products are continuously developed towards the trend of lightweight and high performance. Therefore, an optical imaging system capable of improving the imaging quality of mobile electronics as well as minimizing the overall size of the camera lens assembly equipped therewith is urgently needed.